Hello there!
My dad did a test with 'LivingDNA' (which has quite an iffy reputation, for being heavily biased towards the British Isles, in terms of their 'ethnic' matches).
His paternal side is heavily English; we have traced his paternal line back to the mid 19th Century in SE England. Yet, his Y-DNA came back as being R-DF13, a subclade of r1b. This specific subclade is most prevalent in Ireland, followed by Wales, Scotland & Brittany.
It is also found in England, but to substantially smaller extent. Now my knowledge was that the eastern English had identical maternal DNA, to say the Welsh & Irish, being r1b, but where they differed was with the Y-DNA, which in the case of the former group, was firmly in r1a territory; dominant in Northern Germany, Denmark, etc. Obviously this was down to the fact that the majority of those who made the perilous journey across the North Sea to the east coast of England were men, who would then intermarry with the 'local' Romano-British females.
Of course, England is not predominantly Germanic in terms of admixture, but it seems unusual, that considering the location of which we have traced our patrilineal line back to (Essex, Hertfordshire), that this is not of Anglo-Saxon origin.